|Publication number||US7265077 B1|
|Application number||US 11/462,240|
|Publication date||Sep 4, 2007|
|Filing date||Aug 3, 2006|
|Priority date||Feb 10, 2005|
|Also published as||US7087265|
|Publication number||11462240, 462240, US 7265077 B1, US 7265077B1, US-B1-7265077, US7265077 B1, US7265077B1|
|Inventors||Bryan A. Netsch|
|Original Assignee||Netsch Bryan A|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (23), Referenced by (4), Classifications (20), Legal Events (4)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This application is a continuation-in-part of application Ser. No. 10/906,244, filed Feb. 10, 2005, now U.S. Pat. No. 7,087,265.
The disclosure relates to hidden or latent full color images and to devices containing the images and means capable of developing the images.
Relatively inexpensive novelty items containing hidden images are produced in large quantities and are used in a variety of applications including game pieces, food packaging prizes, educational children's books and the like. Many of these items contain hidden images. The images may be developed or revealed by applying a liquid or solid developer to the hidden image area of the object, by removing an opaque coating over the image, by heating the image, by rubbing the image to rupture microcapsules containing color developer or colorant and the like. The disadvantage of many of these items is that the image is often blurry, weakly developed and/or does not contain vibrant well defined colors. Another disadvantage of such objects is that the developer or solvent is often toxic or hazardous and thus could be dangerous when used by unsupervised children or infants.
Color forming dyes which are applied to a substrate in the form of microcapsules have limited application for producing images as the microcapsules are relatively fragile and care must be taken to assure that the microcapsules are applied to the substrate without substantial breakage of the microcapsules. Scuffing the printed surface or exposing the printed surface to heat may prematurely rupture the microcapsules. Thus it is difficult to print latent or hidden images using microcapsules containing the reactive components by four color process techniques. Another disadvantage of microcapsules containing the color former or developer compound is that the developed colors are somewhat diluted by the presence of the microcapsule material and are less vibrant than colors developed in the absence of microcapsules.
In addition to the use of microcapsules, chromogenic compounds have been dispersed in a wax medium and applied to a substrate. The wax medium, however, may dilute or blur the color forming compounds and delay or retard the speed the image develops. As with the microcapsules described above, scuffing or exposing the wax medium to heat may cause premature release of the color forming compounds or developer. Accordingly, there remains a need for cost effect devices and systems capable of applying color forming compounds to substrates to produce full color images having improved color vibrancy.
Considering the foregoing, the disclosure provides a latent image developing system, a novelty kit, and an ink composition for printing latent images on a substrate. The latent image developing system includes a first substrate containing a colorless image deposited on a first surface thereof. A developer component is provided that is reactive with the colorless image to provide a visible image. The developer component is selected from a developer instrument, a developer finger paint, a developer coating on a first surface of a substantially transparent substrate for adhesive attachment to the first substrate, and a combination of one or more of the developer instrument, the developer finger paint, and the developer coating. The latent image developing system optionally includes, an image blocking instrument for concealing at least a portion of the visible image. The image blocking instrument includes a blocking composition applicator and an aqueous mixture of blocking composition and water.
In another aspect the disclosure provides a novelty kit having therein a first substrate containing a colorless image deposited on a first surface thereof. A developer component is included in the novelty kit that is reactive with the colorless image to provide a visible image. The developer component selected from a developer instrument, a developer finger paint, a developer coating on a first surface of a second substrate for adhesive attachment to the first substrate, and a combination of one or more of the developer instrument, the developer finger paint, and the developer coating. An optional component of the novelty kit is an image blocking instrument for concealing at least a portion of the visible image. The image blocking instrument includes a blocking composition applicator and an aqueous mixture of blocking composition and water.
Yet another embodiment of the disclosure provides an ink composition for printing a colorless image on a first substrate. The ink composition includes a substantially colorless flexographic ink base made of a binder resin and from about 5 to about 20 percent by weight of a substantially colorless compound dissolved in a solvent portion of the ink base for printing the colorless image on the first substrate. The ink composition is reactive with a developer component selected from a developer compound dissolved in from about 35 to about 85 percent carrier fluid, a water-base developer finger paint, a developer coating on a first surface of a second substrate for adhesive attachment to the first substrate, and a combination of one or more of the developer instrument, the water-base developer finger paint, and the developer coating. The developer component is effective to provide a visible image on the first substrate when reacted with the ink composition.
An important advantage of embodiments of the disclosure is that black and white, spot color, or full color images may be developed rapidly which have excellent resolution and/or possess vibrant colors with high color intensity without having to apply relatively heavy ink coverage to a substrate to obtain the high color intensity images. Still another advantage of embodiments of the disclosure is that developer coating on the second substrate may provide images that are substantially permanent and cannot be readily altered or modified thereby improving the security of the developed images. Another advantage of the embodiments of the disclosure is that alternate method of developing an image may be used with the same latent image ink composition to provide a variety of novelty items. A further advantage of the compositions and systems described herein is that each of the components is substantially colorless until applied to a previously printed or coated substrate. Accordingly, the developer component and ink compositions may not stain or mark clothing, skin, furniture, walls or other objects. Still another advantage of the embodiments described herein is the ability to provide clandestine messages by selective blocking development of latent images on a substrate.
The above and other features of the disclosed embodiments may be further described in the following detailed specification in conjunction with the accompanying drawings in which:
In the methods and systems described herein, components of the methods and systems may be deposited or printed on a substrate, preferably as a latent or substantially invisible image or as a substantially invisible developer component. By “substantially invisible” means that the deposited area may have a slight discoloration or may vary in tint from the adjacent substrate, however, to the casual observer, the variation in tint or coloration is so slight as to be essentially imperceptible prior to developing the image by the techniques described herein.
In a first embodiment of the disclosure illustrated in
The latent image 12 may be printed on the substrate 10 by a wide variety of printing techniques including, but not limited to, flexographic, lithographic, sheet fed, web offset, rotogravure, gravure, screen printing, ink jet printing, and variable image printing techniques. Printing techniques which may be used to print the latent image 12 on the substrate 12 include spot printing and process printing. A particularly preferred printing technique is 3 or 4 color process printing. Process printing may be used with a web-offset or flexographic printer to deposit the latent image 12 on the substrate 10. When developed, 3 or 4 color process printed images may be more visually pleasing than spot printing the images because a wider variety of colors may be printed using process printed images. Also, process printed images enable use of lower weights of ink to be printed while providing higher intensity of printed images.
In the case of printing the latent image 12 with a variety of substantially colorless chromogenic ink formulations, a flexographic printing technique is particularly suitable and provides the latent image 12 having a image thickness ranging from about 0.25 micron to about 3 microns. Thicker or thinner layers of the image 12 may be used to provide variation in color intensity upon development of the image.
A suitable flexographic ink composition for providing the latent image 12 may include a solvent-based ink base suitable for use in a flexographic printing process. Ink compositions, as described herein, are substantially colorless and adaptable to four color processing operations. The substrate 10 containing the latent image 12, before development is shown in
With respect to the embodiments illustrated in
Accordingly, the ink base may include a colorless dye, a polyamide resin, and one or more of ethanol, heptane, n-propyl acetate, isopropyl alcohol, n-propanol, and nitrocellulose. Such ink compositions may contain from about 1 to about 10 percent by weight colorless dye, from about 10 to about 45 percent by weight polyamide resin, from about 10 to about 45 percent by weight ethanol, from about 5 to about 15 percent by weight heptane, and from about 0.5 to about 10 percent by weight of one or more of the other components.
The colorless dye may be dissolved in a solvent portion of the ink base using conventional high shear mixing with heating. After the colorless dye is dissolved in the solvent portion of the ink base, the dissolved dye and a varnish portion of the ink base are then mixed at relatively low speeds with other components of the ink base. Suitable colorless dyes may be available from Intense Printing, Inc., of Dallas, Tex. under the trade names IPI 2537 YL (yellow), IPI 21115 BK (black), IPI 32212 BL (blue), IPI 32219 BLS (higher solubility blue), and IPI 854 RD (red). Exemplary ink formulations containing one or more of the foregoing dyes are contained in the following tables.
Colorless Ink Component
Weight Percent Range
Polyamide Resin Flexographic Ink Base
The foregoing ink formulation is generally considered a solvent-base ink formulation. However, the colorless dyes may also be used with a substantially aqueous-base ink formulation. As with the solvent-base formulation given in table 1, the colorless dye for the aqueous-base formulation may be dissolved in a solvent portion of the ink base containing a minor amount of the copolymer using conventional high shear mixing with heating. After the colorless dye is dissolved in the solvent portion of the ink base, the dissolved dye and the remaining copolymer portion of the ink base are then mixed at relatively low speeds. A suitable aqueous-base ink formulation is contained in the following table 2.
Colorless Ink Component
Weight Percent Range
Styrene/acrylic copolymer suspended in water
Dipropylene glycol monomethyl ether
While the foregoing compositions are particularly suitable for the first embodiment of the disclosure, other colorless ink formulations may be used with suitable developer components and blocker compounds to provide the benefits and advantages described herein. Additional, two or more of the dyes may be combined to provide higher intensity color development. For example, a relatively low solubility blue dye IPI 32212 BL) mixed with a relatively high solubility blue dye (IPI 32219 BLS) may provide a greater color intensity than either one of the dyes alone at a same dye concentration as the concentration of the mixed dyes.
Additional components may be present in the ink formulations including, but not limited to, film formers, fillers, binders, waxes, non-volatile diluents, uv absorbers, antioxidants and starch particles (stilt). Film formers, which may be used include polyvinyl pyrrolidone, polyvinyl alcohol, starch, grafted starch and the like. In addition, the film former provides excellent rheological properties to the ink formulation that may permit the image to be spot coated or printed using conventional flexographic printing equipment. The film former may also aid in maintaining the chromogenic compound at the surface of the substrate 10 so that solvent interaction with a developer composition produces a sharp image on the surface of the substrate 10.
The binders with may be used to prepare the ink formulations for printing on the substrate 10 may be selected from partially or fully hydrolyzed polyvinyl alcohols, natural or modified starches, acrylics and the like. A preferred binder is a modified starch available under the trade name PENSIZE 730 binder available from Penford Products of Cedar Rapids, Iowa.
Fillers which may be included in the ink formulations may be selected from any number of compounds such as calcium carbonate, wheat starch, rice starch, nitrous cellulose, and/or polyamide resin.
Diluents may also be used to reduce the viscosity of the ink formulation for printing and to reduce curling of the coated substrate. Suitable diluents include, but are not limited to, ethyl alcohol, isopropyl alcohol, and methyl glucocide.
The amount of ink formulation deposited or printed on the substrate 10 may vary with the characteristics of the substrate 10 and the use thereof. Higher coating weights may be used for more porous substrates 10, whereas lower coating weights may be acceptable for substantially non-porous substrates 10. For many substrates, it is desirable to apply a sub-layer between the substrate 10 and the latent image 12 in order to reduce the absorbence of ink into the substrate 10 or reduce the contrast between the latent image 12 and the non-printed portions of the substrate 10 adjacent the printed areas. Such sublayer may comprise a pigmented coating of ink such as an amine solubilized acrylic, overprint varnish or other material which substantially reduces the contrast between the substrate 10 and the latent image printed 12 printed on the substrate 10. A preferred sublayer is a starch-based coating containing TiO2 or CaCO3 plus an optical brightener. It is particularly desirable to use a sublayer which provides a difference in reflectance between the substrate 10 and the latent image 12 of less than about five percent.
The preferred coating weights of the latent image 12 printed on the substrate 10 may range from about 0.25 to about 2 pounds per 1300 square feet. Accordingly, the thickness of the latent image 12 after drying may range from about 0.25 micron to about 3 micron. The preferred thickness of the latent image 12 is about 0.65 micron.
Before the substrate 10 is printed with the latent image 12, it may be desirable to coat an opposing surface of the substrate 10 with a varnish or stiffening material to reduce substrate 10 curling particularly when the substrate 10 is a thin web such as paper or a plastic film. A particularly suitable varnish is a flexo applied sizing varnish.
The ink formulations provided above in Table 1, may be spot printed on a substrate 10 using a COMPCO COMAMANDER printer with 10-11 billionths of a cubic meter (BCM), 200 line anilox rolls with a doctor blade or a NILPETER printer with 8-9 BCM, 300 anilox rolls. Other printing techniques may also be used to provide the latent image 12 on the substrate 10 according to the disclosed embodiments and the amount of base ink to dye may be adjusted for lower or higher BCM anilox rolls.
In an alternative embodiment described in more detail below, the substrate 10 may include a latent image 12 that includes an adhesive component for attaching a first surface 24 of the image 12 to a second substrate containing a developer compound coated thereon.
In order to develop the latent image 12, a developer component reactive with the latent image 12 is provided. The developer component may be selected from a developer instrument 26, a developer finger paint, a developer coating on a first surface of a second substrate, and a combination of one or more of the developer instrument 26, the developer finger paint, and the developer coating. The developer instrument 26, illustrated in
In a second embodiment of the disclosure, prior to developing the latent image 12, a secret message may be written on the latent image 12 as indicated by the broken-line rectangle 30 in
A suitable blocking composition for blocking development of the latent image 12 in the rectangle 30 may an amine compound dissolved in water. A particularly suitable amine compound is triethanolamine. Accordingly, the blocking formulation may include from about 15 to about 35 weight percent triethanolamine and from about 65 to about 85 weight percent water. Above this range, the blocking composition may be less effective. While not desiring to be bound by theory, it is believed that the blocking composition may absorb less into the substrate above about 35 wt. %. Accordingly, an optimal blocking formulation may include from about 20 to about 25 wt. % triethanolamine and from about 75 to about 80 wt. % water.
In accordance with the foregoing embodiment, a user may encode secret messages by blocking development of selected areas of the latent image 12 using the blocking marker 32. The secret messages 38 may only be revealed by another user having a developer component suitable for developing the latent image as shown in
The developer composition for developing the latent image 12 using the developer instrument 26 may be selected from acidic clays and unsubstituted or ring-substituted phenols, phenolic resins, sulfone compounds, alkylhydroxybenzoic acid compounds and salicylic acid or salicylate and their metal salts or combinations of two or more of the foregoing. A suitable color developer composition for developing latent images 12 may be a benzoic acid compound dissolved in an alcohol carrier fluid. For example, the developer composition may include from about 5 to about 15 weight percent salicylic acid, from about 65 to about 85 percent by weight isopropyl alcohol and from about 10 to about 20 percent by weight bisphenolic compounds.
Another developer composition that may be used in the developer instrument includes from about 30 to about 65 percent by weight metal chloride, from about 10 to about 25 weight percent water, from about 10 to about 25 weight percent propylene glycol, and from about 10 to about 25 weight percent isopropyl alcohol. While zinc chloride is a particularly desirable metal chloride, other metal cations may also be used, such as cadmium (III), zirconium (II), cobalt (II), strontium (II), aluminum (III), copper (III), and tin (II).
A third embodiment of the disclosure is illustrated in
Substantially transparent films useful as the first substrate 10 or second substrate 40 preferably have a thickness that may range from about 10 to about 100 microns. Particularly preferred films are substantially optically clear, about 50 micron thick, and are print receptive films. Such films include, but are not limited to, polyethylene terephthalate (PET) films available from Mitsubishi Polyester Film LLC of Greer, S.C., under the trade name HOSTAPHAN 4400 and from SKC, Inc. of Covington, Ga. under the trade name SH-81.
The length and width of the transparent film is not critical to the invention and may be any suitable length and width. The film may also be cut into selected shapes for application to the first substrate. The terms “substantially transparent” and “substantially optically clear” mean that details of objects or images covered by such a film are essentially visible through the film as opposed to blocking all or a substantial portion of the object or image from view.
For the purpose of illustration only, the second embodiment will now be described with the latent or hidden image 12 being printed on an opaque substrate 10 and the developer layer 42 being coated onto a substantially transparent substrate 40. It will be recognized by those of ordinary skill in the art that the latent or hidden image 12 may be printed on the substantially transparent substrate 40 and the developer layer may be included on an opaque substrate 10 or on another substantially transparent substrate.
The layer 42 also includes a micro-encapsulated organic solvent which may be selected from compounds such as alcohols, dioctylphthalate (DOP), di-isooctylphthalate (DIOP), isopropyl myristate (IPM), isopropyl palmitate (IPP), soybean oil (unepoxidized), castor oil, linseed oil, olive oil, mineral oil, petrolatum (otherwise known as petroleum jelly or paraffin jelly) and the like or mixtures thereof. The solvent is preferably compatible with the chromogenic compound and the developer composition. A preferred micro-encapsulated solvent is available from Schenectady International, Inc. under the trade name HRJ-15151. The layer 42 may include from about 20 to about 50 percent by weight of the micro-encapsulated solvent based on the dry weight of micro-encapsulated solvent in the layer 42.
It is preferred that microcapsules for the micro-encapsulated solvent have relatively thin walls so that rupture of the microcapsules to release the solvent may be readily achieved. However, the walls of the microcapsules should not be so thin that it is difficult to coat the layer 42 on a substrate surface without rupturing a substantial portion of the microcapsules. Also, it is desirable that premature rupture of the micro-capsules not occur when handling the second substrate 40. Accordingly, a preferred microcapsule wall content may range from about 5 to about 10 percent by weight of the total weight of the microcapsule and solvent. The term “wall content” means the weight percentage of the microcapsule that is provided by the walls containing the solvent.
The wall thickness of the microcapsules for a particular wall content may vary according to the size or diameter of the microcapsules. Typically, the micro-capsules have a diameter ranging from about 5 to about 10 microns. It is also preferred that the micro-encapsulated solvent be readily dispersible in an aqueous fluid for mixing with the developer compound described above and an adhesive, as described below.
Another component of layer 42 is an adhesive for retaining the developer compound and micro-encapsulated solvent on the second substrate 40 and for attaching the second substrate 40 to the first substrate 10. A preferred adhesive for use as the continuous phase of layer 42 is a pressure sensitive adhesive which enables substrates 40 and 10 to be fixedly attached to one another during the image developing step. A preferred pressure sensitive adhesive is an aqueous-based adhesive such as an adhesive available from Dyna-Tech Adhesives of Grafton, West Virginia under the trade name TECHCRYL 6136. The amount of pressure sensitive adhesive in layer 42 may range from about 20 to about 60% by weight of the total dry weight of layer 42.
Other minor components used to provide layer 42 include, but are not limited to an anti-foam agent and a filler such as hydrophobic silica. The amount of the other components is typically less than about 0.5 weight percent of a formulation containing the adhesive and microencapsulated solvent components.
In order to protect layer 42 containing an adhesive, the developer composition, and the micro-encapsulated solvent for the chromogenic compounds and developer composition, a cover web or release liner 46 as illustrated in
A process for developing a latent or hidden image is shown in the sequence of
In order to rupture at least a portion of the microcapsules in the layer 42 and release sufficient solvent to interact with the developer composition and image 12, a second surface 50 of the second substrate 40 or a second surface 52 of the first substrate 10 may be rubbed with a fingernail, coin, or other substantially rigid object 54 that is capable of rupturing the microcapsules in layer 42. As the surface 50 or 52 is rubbed, microcapsules containing the solvent are ruptured providing an amount of solvent suitable for causing reaction between the chromogenic compound in image 12 and the developer composition in layer 42. However, because the solvent is contained in microcapsules that are attached to layer 42, there is no liquid solvent or developer to spill or otherwise come in contact with a user's hands or clothing.
The progress of image development as substrate 40 is attached to substrate 10 is illustrated by reference to
In the alternative embodiment, the first surface of substrate 10 may include a pressure sensitive adhesive in addition to the latent image 12. In such an embodiment, layer 42 on substrate 40 may be provided by dispersing the developer composition and micro-encapsulated solvent in a suitable aqueous binder. Contact between substrate 10 and substrate 40 and rupture of the microcapsules to release solvent and develop the image is generally in accordance with the method described above with reference to
In yet another alternative embodiment, the first surface of substrate 10 may include the micro-encapsulated solvent, described above, in addition to the latent image 12. In such an embodiment, layer 42 on substrate 40 may be provided by dispersing the developer composition in the pressure sensitive adhesive that is applied to substrate 40. Contact between substrate 10 and substrate 40 and rupture of the microcapsules to release solvent and develop the image is generally in accordance with the method described above.
In an alternative embodiment, a portion of the image 12 may be developed by a user's fingers by dipping one or more fingers in a developer finger paint device 43 illustrated in
Other embodiments of the disclosure include developing the image 12 or 56 on the substrate 10 by a combination of use of the developer instrument 26, the developer finger paint 47, and the substrate 40 containing the developer composition. In such an embodiment, a first portion of the image 12 or 56 may be developed with the developer instrument 26, or developer finger paint 47, and a second portion of the image 12 or 56 may be developed with the developer layer 42 on substrate 40 by attaching substrate 40 to the second portion of the image 12 or 56. In any of the foregoing embodiments, the marker 32 containing the blocking composition may be used to provide secret or encoded messages as described above.
A fourth embodiment of the disclosure is illustrated in
A printing technique for applying the developer layer 62 to the substrate 60 may include any of the well known printing and substrate coating techniques. Application of the developer composition may be over the entire substrate 60 or may be in selected areas of the substrate 60. Ink jet printing, screen printing, rotogravure printing, flexographic printing, and the like may be used to apply the developer layer 62 to selected portions of the substrate 60. Roll coating, blade coating, dipping, spray coating, and the like may be used to coat an entire portion of the substrate 60. The amount of developer composition applied to the substrate 60 to provide the developer layer 62 may range from about 0.35 micron to about 4.5 microns or more. The developer composition may be applied evenly over the entire substrate 60 or different amounts of developer composition may be applied to different portions of the substrate to provide variations in the intensity of the images and the speed at which the images become visible to provide different image effects.
An advantage of the developer composition in combination with colorless chromogenic compositions is that lighter weight color developer laydown may be used to provide fine detail images and images having vibrant colors, whereas conventional compositions require heavy weight laydown amounts of developer to provide image intensities that only approach the image intensities of the disclosed embodiments. Accordingly, a flexographic process using a 200-400 line anilox roll may apply sufficient developer composition to provide high resolution images upon application of a colorless chromogenic composition to the developer layer 62.
Developer compositions that may be used for the developer layer 62 include, but are not limited to, acidic clays and unsubstituted or ring-substituted phenols, phenolic resins, sulfone compounds, alkylhydroxybenzoic acid compounds and salicylic acid or salicylate and their metal salts or combinations of two or more of the foregoing. Accordingly, a preferred color developer composition may include a benzoic acid, 2-hydroxy-3,5-bis(1-phenylethyl)-, zinc salt and (9,10-dihydro-9-oxa-10-phosphophenanthrene-10-oxide) copolymer with α-methylstyrene, styrene, and polyvinylalcohol. Of the foregoing, a zinc salicylate resin may be particularly suitable as a component of the developer composition. While zinc is the preferred cation, other metal cations may also be used, such as cadmium (III), zirconium (II), cobalt (II), strontium (II), aluminum (III), copper (III), and tin (II).
A formulation that may be used to print or apply the developer composition onto the substrate 60 may include binders, pigments, surfactacts, water and the like. A particularly useful formulation is provided in the following table.
Weight Percent Range
PENSIZE Starch binder
SATINTONE 5 HB pigment
Zinc salicylate resin
Another color developer formulation that may be used is a substantially aqueous color developer composition. The substantially aqueous color developer composition includes from about 30 to about 65 wt. % zinc chloride, from about 10 to about 25 wt. % water, from about 10 to about 25 wt. % propylene glycol, and from about 10 to about 25 wt. % isopropyl alcohol.
In order to provide an image on the substrate 60, a marking instrument 66, or plurality of marking instruments 66 containing different substantially colorless chromogenic compounds may be used to apply the chromogenic compounds to the developer layer 62 to produce a visible image 68 as shown in
A formulation containing the colorless chromogenic compound for use in the marking instruments 66 may include from about 75 to about 95 percent by weight alcohol, from about 2 to about 15 percent by weight of the chromogenic compound, and from about 1 to about 10 percent by weight glycol ether. Alcohol solvents which may be used, include, but are not limited to, C1 to C4 alkyl alcohols such as is ethanol, methanol or isopropanol, n-propyl alcohol and the like. Other solvent that may be used include, but are not limited to, C1 to C4 alkyl ethers, C1 to C4 alkyl esters, ketones and acetates. Ketones may include methyl ethyl ketone and acetone. The embodiments described herein also contemplate colorless chromogenic compounds that may be applied with fingers instead of the marking instruments 66.
Prior to applying chromogenic compounds to the developer layer 62 using one or more different color markers 66, a blocking composition may be applied to the developer layer 62 to prevent development of color upon application of the chromogenic compound to the developer layer 62. Accordingly, the blocking instrument 32 containing the blocking composition described above may be used to provide blocked areas 72, illustrated in outline in
Having described various aspects and exemplary embodiments and several advantages thereof, it will be recognized by those of ordinary skills that the disclosed embodiments are susceptible to various modifications, substitutions and revisions within the spirit and scope of the appended claims.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US2293072 *||Mar 29, 1940||Aug 18, 1942||Rit Products Corp||Dye package|
|US3900215||Jan 22, 1973||Aug 19, 1975||Fuji Photo Film Co Ltd||Record sheet|
|US4212393 *||Dec 29, 1978||Jul 15, 1980||Lenkoff Leon G||Magic pictures|
|US4321093||Apr 4, 1980||Mar 23, 1982||The Standard Register Company||Moisture-set color developer ink|
|US4477593 *||Mar 2, 1982||Oct 16, 1984||Lockley Services Pty. Ltd.||Sheet printed with invisible inks, developers and erasure compounds _for invisible inks|
|US4557618||Dec 22, 1982||Dec 10, 1985||Pentel Kabushiki Kaisha||Ink and eraser of the ink|
|US4865938||Dec 18, 1987||Sep 12, 1989||Brother Kogyo Kabushiki Kaisha||Photo and pressure sensitive recording media comprising an adhesive agent|
|US4943089||May 17, 1989||Jul 24, 1990||Reardon David C||Fingerprint sensitive pad|
|US5075278||Mar 4, 1991||Dec 24, 1991||Vassiliades Anthony E||Chromogenic copy systems and methods|
|US5234344 *||Dec 28, 1987||Aug 10, 1993||Stry-Lenkoff Company||Book package|
|US5415434||Jan 11, 1994||May 16, 1995||Kawashima; Kiyoharu||Printed matter|
|US5485792||Jul 7, 1995||Jan 23, 1996||Western Publishing Co., Inc.||Latent image development system|
|US5492558||Oct 3, 1994||Feb 20, 1996||Binney & Smith Inc.||Color changing compositions for highlighters|
|US5503665||Oct 4, 1994||Apr 2, 1996||Binney & Smith Inc.||Latent image compositions|
|US5814579 *||Aug 6, 1996||Sep 29, 1998||The Standard Register Company||Multicolor printing system|
|US6114281||Jan 27, 1998||Sep 5, 2000||Nocopi Technologies, Inc.||Method and compositions for authenticating a product or document|
|US6162485||May 7, 1998||Dec 19, 2000||Wallace Computers Services, Inc.||Fingerprinting system and method|
|US6293667||Oct 2, 1998||Sep 25, 2001||Zeneca Limited||Process for producing an image on a substrate|
|US6905539||Jul 15, 2003||Jun 14, 2005||Sanford L.P.||Black eradicable ink, methods of eradication of the same, eradicable ink kit, and eradicated ink complex|
|US6967069 *||Apr 9, 2003||Nov 22, 2005||Xerox Corporation||Photoconductive imaging members|
|US20030236165||Jun 25, 2002||Dec 25, 2003||Appleton Papers Inc.||Product authentication|
|CA2149946A1||May 23, 1995||Nov 24, 1996||Wallace Computer Services||Hidden entry system and image-developing device therefor|
|EP0017889A1||Apr 8, 1980||Oct 29, 1980||Kores Holding Zug AG||Writing system|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US9061217 *||Sep 11, 2014||Jun 23, 2015||Mattel, Inc.||Projectile launcher|
|US20080248950 *||Oct 3, 2007||Oct 9, 2008||Ibrahim Katampe||Ink and Developer System|
|US20140272096 *||Mar 15, 2013||Sep 18, 2014||Hallmark Cards, Incorporated||Method and apparatus for revealing a hidden element|
|US20150079874 *||Sep 11, 2014||Mar 19, 2015||Mattel, Inc.||Projectile Launcher|
|U.S. Classification||503/201, 106/31.16, 503/216, 503/226, 503/205|
|International Classification||B41M5/24, B41M5/20|
|Cooperative Classification||B41M5/1455, B41M3/001, C09D11/037, B41M5/1555, B41M5/132, B41M3/005, B41M5/124, B41M5/165, B41M5/136, B41M5/155|
|European Classification||C09D11/037, B41M3/00H, B41M3/00C|
|Feb 8, 2011||FPAY||Fee payment|
Year of fee payment: 4
|Apr 17, 2015||REMI||Maintenance fee reminder mailed|
|Aug 26, 2015||FPAY||Fee payment|
Year of fee payment: 8
|Aug 26, 2015||SULP||Surcharge for late payment|
Year of fee payment: 7